[shearej]

18 months ago I brewed a Flanders Red.  Finally tasted it.  Turned out great with nice acetic character.  However, the body was a bit too thin.  What are some tricks you all use to build body (that is, leave dextrins) in sour ales?  My understanding is with mixed culture fermentations the Brett and peddiococcous consume those dextrins that provide body in non-sour ales. 

[klickitat jim]

This will be no help. I look at body in sour beer like brilliant clarity in an IPA. I don't expect it. I shoot for effervescent on the carbonation and call it good.

Someone may have a trick, but the few I've heard of either don't seem plausible or they require some sacrifice of other attributes of a good sour. Same as the story with making crystal clear IPAs. Tough to do without cutting the hop aroma.

[morticaixavier]

I'm with Jim here. it's just not part of the style. you can create some body like mouthfeel with higher carbonation though.

[bboy9000]

I'm with Jim here. it's just not part of the style. you can create some body like mouthfeel with higher carbonation though.

^This. 

Some perception of body in a commercial example of a Flanders Red may be due to low levels of diacetyl from the pediococcus but I wouldn't try to intentionally get this I'm the beer.

[chezteth]

I'm with Jim here. it's just not part of the style. you can create some body like mouthfeel with higher carbonation though.

I agree with this as well.

[reverseapachemaster]

If you find Flemmish reds with body it's because they have been backsweetened or blended with non-sour beer. It's just not traditionally appropriate for the style.

[dmtaylor]

I hate to sound like a jerk but I get more body from less carbonation.  However more carbonation can tickle and excite the palate.  For instance last night I drank a homemade cider that is uncarbonated, and it was just too bland, so I SodaStreamed (carbonated) a few ounces of water and blended it with my cider to tickle the tongue just a wee more.  This doesn't improve the body at all, but does make the flat cider more pleasurable to drink.

You could play with lactose additions, but I'd agree with the others that it's really not appropriate or expected for a sour beer style.

[bboy9000]

If you find Flemmish reds with body it's because they have been backsweetened or blended with non-sour beer. It's just not traditionally appropriate for the style.

I believe blending sour beers with newer, non-sour beer is actually a traditional practice. On the other hand the sweeter sour beers that people like today are often back sweetened with artificial sweeteners like aspartame .  From what I've read it would be acceptable to add a little body by blending in some younger beer. I think a little bit of body in a Flanders red would be fine as it's not a Lambic or an American sour ale.

EDIT:  to get back on topic to the original poster, if the acetic character is a little too strong for you maybe try to reduce the amount of oxygen that makes it into the fermentation vessel. Avoid opening the fermentation vessel at all costs. When aging the beer fill The fermentation vessel as full as you can. For example my sour ale in secondary is filled all the way up to the neck not just the shoulders of the carboy.  Also any time I open it to take a gravity reading (which is  every 2-3 months) I flush the air space with CO2.  All the acetic acid is probably diminishing body as you suspect.

As you mentioned earlier another thing to consider is your grain bill.  Maybe try using some Munich malt in your recipe or some melanoidin malt.

[ynotbrusum]

Regarding Flanders Reds - I have a three or four year Solera going...every six months or so I brew a new beer that is blended based on proportional tasting.  One time I added a tart cherry wine base to the mix in a fermenter with a straight Brett pitch!  Nothing wrong with blending - the Belgians consider that the highest degree of the "art" in artisanal.

[reverseapachemaster]

If you find Flemmish reds with body it's because they have been backsweetened or blended with non-sour beer. It's just not traditionally appropriate for the style.

I believe blending sour beers with newer, non-sour beer is actually a traditional practice. On the other hand the sweeter sour beers that people like today are often back sweetened with artificial sweeteners like aspartame .  From what I've read it would be acceptable to add a little body by blending in some younger beer. I think a little bit of body in a Flanders red would be fine as it's not a Lambic or an American sour ale.

I did a poor job of stating my point. I did not mean to suggest blending or sweetening the sour beer is not traditional.

What I should have said is:

A Flemish red would not typically have much body unless it has been backsweetened or blended with non-sour beer. There is absolutely nothing wrong with blending. I'm not a fan of the reds I've tried that were backsweetened but there is some tradition behind sweetening sour beer as well.

[klickitat jim]

I hate to sound like a jerk but I get more body from less carbonation.  However more carbonation can tickle and excite the palate.  For instance last night I drank a homemade cider that is uncarbonated, and it was just too bland, so I SodaStreamed (carbonated) a few ounces of water and blended it with my cider to tickle the tongue just a wee more.  This doesn't improve the body at all, but does make the flat cider more pleasurable to drink.

You could play with lactose additions, but I'd agree with the others that it's really not appropriate or expected for a sour beer style.

What is body? If you say viscosity, then I agree that co2 doesnt increase the actual thickness of the beer. If body is a feeling of viscocity in the mouth, then I disagree.

[bboy9000]

If you find Flemmish reds with body it's because they have been backsweetened or blended with non-sour beer. It's just not traditionally appropriate for the style.

I believe blending sour beers with newer, non-sour beer is actually a traditional practice. On the other hand the sweeter sour beers that people like today are often back sweetened with artificial sweeteners like aspartame .  From what I've read it would be acceptable to add a little body by blending in some younger beer. I think a little bit of body in a Flanders red would be fine as it's not a Lambic or an American sour ale.

I did a poor job of stating my point. I did not mean to suggest blending or sweetening the sour beer is not traditional.

What I should have said is:

A Flemish red would not typically have much body unless it has been backsweetened or blended with non-sour beer. There is absolutely nothing wrong with blending. I'm not a fan of the reds I've tried that were backsweetened but there is some tradition behind sweetening sour beer as well.

What I meant was there is a difference between blending and back-sweetening.  From what I've read about sour styles and heard in interviews with Jean Van Roy, is that blending is traditional, done to achieve balance.  The sugars in the younger beer come from using raw grains that provide unfermentable (or slowly ferment able) sugars to the beer.  Back-sweetening with sugars (aspartame and saccharine) and syrups is a newer practice meant to attract a younger demographic to Belgian beer (think Bud Light Lime or wine coolers) Yes, both methods add sugar to the finished product but from different sources and for different purposes if my understanding is correct.

http://sourbeerblog.com/designing-and-brewing-a-flanders-red-ale/

https://byo.com/stout/item/2989-flanders-red-style-profile

http://thebrewingnetwork.com/shows/751

http://www.saveur.com/article/Wine-and-Drink/A-Beer-Called-Lambic

[klickitat jim]

According to Jean, if memory serves, the YOUNG beer is a year old. So, I doubt that its all that sweet.

Another though regarding these commercial guys, they make a beer and put it in numerous barrels. Then they taste each barrel (all of the same beer) and find that some are more sour, some less, some have more body some have less, and they select and blend accordingly. Thats not what most of us are doing. In effect, the OP tastes one beer from one barrel and wonders how to get more body. Given how the pros do it, I suppose the answer might be brew it again and next time it might have more body.

[bboy9000]

Given how the pros do it, I suppose the answer might be brew it again and next time it might have more body.

Maybe the OP can try adding some raw wheat, oats or carapils to the recipe.  Re brew, ferment and blend it with the acidic one.  Experiment with 10 oz servings with different ratios until it gets the desired body.

[dmtaylor]

What is body? If you say viscosity, then I agree that co2 doesnt increase the actual thickness of the beer. If body is a feeling of viscocity in the mouth, then I disagree.

Ask a dozen BJCP'ers, you'll receive a dozen different answers.

To me, body is a feeling of viscosity, usually associated with dextrins and any unfermented sugars.  A heavy body is also the opposite of thinness and a very watery quality.  You can carbonate either one, but I would argue that carbonation affects the body more when there are a lot of dextrins and/or sugars.  When you highly carbonate a dextrinous beer, it makes it feel thinner but also more creamy.  When you highly carbonate a very thin, watery beer (or cider or anything else), I would argue that while it doesn't feel like it has any more or less body, the carbonation can disguise the fact that it's otherwise so thin and watery, and so the carbonation entertains the palate in a different manner than affecting the "body".

Understand those are my opinions and mine alone.  I don't care if anyone disagrees.